1. Field of the Invention
The present invention relates to, for example, a substrate processing apparatus of a coating and developing process apparatus and the like, coating and developing a resist solution onto a semi-conductor wafer.
2. Description of the Related Art
In the process of photo-resist processing in semiconductor device fabrication, for example, a substrate such as a semiconductor wafer (hereinafter referred to as xe2x80x9ca waferxe2x80x9d) or the like undergoes exposure of a pattern, heating process, temperature regulating process, and then developing process. A coating and developing process apparatus has been used for such a series of processing.
This coating and developing process apparatus includes various kinds of processing units for individually performing a series of process required for coating and developing process of a wafer, for example, resist coating process applying a resist solution, heating process heating the wafer which has undergone exposing process, temperature regulating process regulating the temperature of the wafer which has undergone the heating process, and developing process performing a developing process to the wafer which has undergone the temperature regulating process. The wafer is carried into and out of each processing unit and transferred between the processing units with a main transfer mechanism.
Incidentally, it is known that a line width of a circuit pattern formed on a surface of a wafer is affected by a time period taken from the completion of the exposing process and the start of the heating process.
However, there is a problem in keeping a time period of transferring the substrate from the aligner to the heat processing portion for performing the heating process constant, since the substrate is kept awaited at an interface portion disposed on the coating and developing processing apparatus side for sending and receiving the substrate with the aligner because of the necessity of the interface portion to get access to a peripheral aligner and to transfer the wafer to the aligner side, apart from transferring the substrate carried out from the aligner into the apparatus.
The present invention is intended to solve such problem and the object thereof is to provide a substrate processing apparatus that is able to keep a time period between the exposing process and the heating process constant so that a circuit pattern formed on the substrate becomes uniform.
To solve the aforesaid problem, the substrate processing apparatus of the present invention performing a developing process to the substrate exposed by the aligner comprising, at least one heat processing portion heat processing the substrate before the developing process, an interface portion disposed between the heat processing portion and the aligner, sending and receiving the substrate between the heat processing portion and the aligner, and a controller controlling a time period taken in transferring the substrate received from the aligner to the heat processing portion through the interface portion before starting the, heating process on the substrate with the heat processing portion so that the time period become approximately constant.
Here, the process of controlling time mentioned above, includes, for example, making the time period constant with deliberately delaying time to start heating process on the substrate by the heat processing portion.
The present invention controls the time period taken in transferring the substrate received from the aligner to the heat processing portion through the interface portion and until the start of the heating process to be approximately constant so that the time taken from after the exposing process until the heating process can be kept constant, as a result, the line width of the circuit pattern formed on the substrate can be kept uniform.
According to an embodiment of the present invention, the heat processing portion has a heat processing plate performing the heating process to the substrate, and a first transferring portion receiving the substrate from the interface portion and transferring the substrate to the heat processing plate, and the controller controls a transferring speed that the first transferring portion transfers the substrate so that the time period taken in transferring the substrate received from the aligner to the heat processing portion through the interface portion before starting the heating process on the substrate with the heat processing portion become approximately constant.
According to an embodiment of the present invention, the heat processing portion has a heat processing plate performing the heating process to the substrate, and a first transferring portion receiving the substrate from the interface portion and transferring the substrate to the heat processing plate, wherein the controller controls a transferring speed that the first transferring portion transfers the substrate so that the time period taken in transferring the substrate received from the aligner to the heat processing portion through the interface portion before starting the heating process on the substrate with the heat processing portion becomes approximately constant. As one form of embodiment, the interface portion has a transferring system transferring the substrate at a constant speed and the controller at least one of allowing the substrate to wait at the first transferring portion for a while and decreasing the transferring speed of the first transferring portion when a transferring time of the substrate received from the aligner and transferred to the heat processing portion through the interface portion is shorter than a predetermined time period, the controller allows the first transferring portion to start the transportation immediately after receiving the substrate when the transferring time is the same as the predetermined time period, and the controller allows the first transferring portion to increase the transferring speed when the transferring time is longer than the predetermined time period. Consequently, the process of time controlling in relation to the present invention can be performed without imposing stress on the interface portion. According to one embodiment of the present invention, the first transferring portion has a portion regulating temperature of the substrate. As a result, the heating process can be constantly performed, and the line width of the circuit pattern formed on the substrate can be kept uniform. According to an embodiment of the present invention, the substrate processing apparatus has a plurality of heat processing portions which are disposed in multiple stages in vertical direction, the interface portion has a transferring system transferring the substrate from the aligner to the heat processing portion and the controller allows the substrate received from the aligner to be transferred to one of the plurality of heat processing portions through the interface portion and controls the transferring speed in the transferring system so that the time period taken by transferring the substrate to the heat processing portion and the time period taken before starting the heating process on the substrate with the heat processing portion become approximately constant Moreover, each of the heat processing portions has the heat processing plate performing the heating process to the substrate, and the first transferring portion receiving the substrate from the interface portion and transferring the substrate to the heat processing plate and it is preferable for the controller to control the transferring time with controlling the transferring speed of the first transferring portion when the transferring time is unable to be adequately controlled with the transferring system. With this embodiment, keeping the substrate awaited at the interface portion side can be avoided. As a result, the time period taken with the substrate to be transferred from the aligner to the heat processing portion can be shortened, while performing the process of controlling time according to the present invention. According to an embodiment of the present invention, the interface portion has a first interface portion disposed adjacent to the heat processing portion and a second interface portion disposed between the first interface portion and the aligner, wherein the first interface has a second transferring portion transferring the substrate between the heat processing portion, and the second interface portion, the second interface portion has a third transferring portion transferring the substrate between the first interface portion and the aligner. With this embodiment, keeping the substrate awaited at the interface portion side can be avoided. As a result, the time period taken with the substrate to be transferred from the aligner to the heat processing portion can be shortened, while performing the process of controlling time in relation to the present invention.
According to an embodiment of the present invention, the interface portion has a first holding portion holding the substrate transferred to the heat processing portion for a while, a second holding portion holding the substrate transferred to the aligner for a while. The second interface portion has a transitional portion holding the substrate transferred between the first interface portion and the second interface portion for a while, a wafer transfer mechanism transferring the substrate by getting access to the heat processing portion, the first and the second holding portions, and the transitional portion. With this embodiment, keeping the substrate awaited at the interface portion side can be avoided. As a result, the time period taken in transferring the substrate can be shortened while performing the time controlling in relation to the present invention.
According to the present invention explained above, the present invention further comprises a signal input port inputting a substrate ejecting signal coming from the aligner and when the controller starts counting time in a process of controlling the time period to be constant in accordance with the substrate ejecting signal inputted in the signal input port the process of time controlling can be performed more precisely and accurately.
The substrate processing method of the present invention performing a heating process in a heat processing portion before performing a developing process to a substrate exposed with an aligner, comprising the steps of transferring the substrate received from the aligner to the heat processing portion, and controlling a time period so that the time period taken in transferring the substrate received from the aligner to the heat processing portion until the heating process is started on the substrate with the heat processing portion becomes approximately constant.
The present invention controls the time period taken in transferring the substrate received from the aligner to the heat processing portion until starting the heating process to be approximately constant so that the time taken from the exposing process until the heating process is performed can be kept constant, and as a result the line width of the circuit pattern formed on the substrate can be kept uniform.
These objects and still other objects and advantages of the present invention will become apparent upon reading the following specification when taken in conjunction with the accompanying drawings.